7-Step Server Service Check Checklist for Reliable UptimeMaintaining reliable uptime requires regular, structured checks of the services running on your servers. This 7-step checklist walks you through essential validation points — from basic reachability tests to deeper health and dependency inspections — so you can catch faults before they impact users.
1. Verify Network Reachability and Port Availability
Before assuming a service is up, confirm that the server and its service ports are reachable.
- Use ICMP ping and traceroute to check basic connectivity and identify routing issues.
- Test TCP/UDP ports directly (for example, with netcat or curl) to confirm the service is accepting connections.
- For services behind load balancers or proxies, test both the direct backend and the public endpoint.
Quick checks:
- ping
- nc -zv
- curl -I http://
2. Confirm Process and Service Status
Ensure the actual service process is running and stable.
- Check system service managers: systemctl status
, service status. - Validate process presence and resource usage: ps aux | grep
, top, htop. - Look for repeated restarts which indicate crashes or failing health checks.
What to watch for:
- Multiple recent restarts in journal logs.
- Worker processes stuck in restart loops.
- Excessive memory growth (possible memory leak).
3. Run Application-Level Health Checks
Application-level checks verify that the service is not only running but functioning.
- Use built-in HTTP health endpoints (e.g., /health, /status) where available.
- Verify core functionality: database connections, authentication, queue processing, storage access.
- Simulate typical user flows lightly (login, read, write) to detect functional regressions.
Example curl check:
- curl -fsS https://service.example.com/health || echo “Health check failed”
4. Inspect Logs and Error Rates
Logs reveal issues that simple checks miss.
- Scan recent logs for ERROR, WARN, or stack traces. Use journalctl, docker logs, or centralized logging (ELK, Loki).
- Check metrics for error-rate spikes (4xx/5xx responses, exception counts).
- Correlate timestamps across services to trace cascading failures.
Tip: search for keywords and sudden volume increases rather than reading every line.
5. Validate Dependency Health and Latency
Services often fail due to unhealthy dependencies.
- Test connectivity and basic queries against databases, caches (Redis/Memcached), message brokers, and external APIs.
- Measure latency and error responses from dependencies. Increased latency can cause timeouts and cascading failures.
- Ensure credentials, TLS certs, and connection pool limits are correct.
Commands:
- redis-cli PING
- mysql -e “SELECT 1”
- curl -I https://api.dependency.com
6. Check Resource Utilization and Limits
Capacity issues degrade service reliability.
- Monitor CPU, memory, disk I/O, and disk space. Look at both host and container levels.
- Verify file descriptor, process, and network socket limits (ulimit).
- Assess autoscaling triggers and current instance counts to ensure headroom for traffic spikes.
Key thresholds:
- Disk usage above 80% — investigate immediately.
- Swap usage — indicates memory pressure.
- High run queue (load average) — CPU contention.
7. Review Configuration, Security, and Backups
Configuration drift, expired credentials, or missing backups can cause prolonged outages.
- Ensure configuration files match expected templates or use a config management diff (Ansible, Puppet).
- Check TLS certificates for upcoming expiration and rotate if within the renewal window.
- Confirm recent successful backups and test restore procedures periodically.
- Review firewall rules and security group settings for unintended changes.
Backup quick-check:
- Verify last backup timestamp and attempt a test restore on a staging environment.
Putting the Checklist into Practice
- Automate: Convert these steps into scripted checks and integrate them with monitoring and alerting systems (Prometheus, Nagios, Datadog).
- Runbook: Document remediation steps for common failures discovered by each check.
- Schedule: Perform comprehensive checks daily or weekly depending on criticality; lightweight checks (health endpoints, process status) should run continuously.
- Postmortem: After incidents, add new checks to the checklist to prevent recurrence.
Maintaining reliable uptime is about combining quick automated checks with periodic manual inspections. Use this 7-step checklist as a baseline, and adapt it to your stack and operational practices.
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